This proposal is a request for funds to acquire a 500 MHz Fourier transform (FT)-nuclear magnetic resonance (NMR) spectrometer equipped with accessories which will provide state-of-the-art one and two-dimensional proton and carbon- 13 NMR capabilities for the Department of Chemistry at The University of Michigan. Acquisition of this instrumentation is urgently needed for two-dimensional COSY and NOESY studies in the areas of bioorganic, bioinorganic, synthetic, and biophysical chemistry by the PI and seven other major users who hold a total of 10 active NIH-sponsored research grants. Specific projects include: (1) synthetic and mechanistic studies of biologically active natural products and carcinogenic polycyclic aromatic hydrocarbons, (2) synthesis and characterization of Fe/S and Fe/Mo/S cluster analogs of the active centers of non-heme iron proteins and nitrogenase, (3) conformational studies of enzyme substrates and products using 2-D NMR, (4) studies on the recognition of peptides by monoclonal antibodies, (5) alkaloid synthesis via azide cyclizations and 2-azallyl anion chemistry, (6) structural definition of electron transfer proteins, (7) NMR studies of paramagnetic metal centers in the photosynthetic membrane and in model solutions, and (8) synthesis of potential anti-canccr, anti-viral and anti-parasitic nucleosides and analogs.